Three gang leaders were sentenced to death yesterday and three others got the ultimate penalty - with a two-year reprieve - as courts in Chongqing municipality began a series of organized-crime trials.

Yang Tianqing, 35, was given the death sentence after he was convicted of murder, assault, extortion, coercive business practices and other charges linked to "mafia-style gang" operations, according to a statement issued by the No 1 Intermediate People's Court in China's most populous city.

"This organization illegally controlled the Yubei district ... carried out illegal criminal activities against land and construction developers and coerced ordinary people. Their influence has been odious," the court said on its website.

Liu Chenghu, an important member of Yang's gang, was also sentenced to death after he was convicted of five charges, including running a "mafia-style" organization.

Two other members of the crime syndicate were sentenced to death with reprieves, meaning they will not be immediately executed and that there is a chance they may have their sentences commuted to life in prison. Five other gangsters received jail terms, ranging from 11 years to life.

Meanwhile, the municipality's No 3 Intermediate People's Court handed down the death penalty to Liu Zhongyong after he was convicted of organizing criminal gangs and murder.

Liu was also found guilty of running illegal coalmines in suburban Chongqing and was held responsible for two cave-ins - in 2006 and 2008 - that killed three workers.

His 22-member gang was responsible for the killing of one person and injuring at least four others in the city last year, a court statement said.

Liu's right-hand man, Zheng Xin, was sentenced to death with a two-year reprieve.

A total of 20 other members of Liu's crime family were jailed for between one and 17 years.

More than 1,500 suspects linked to organized crime groups, including more than a dozen senior police officers and judicial officials, have been arrested since June 20, when the municipality launched its largest-ever crackdown on mafia-style gangs.

Wen Qiang, who became Chongqing's top judicial official last year after 16 years' service as a deputy police chief, is among those facing the courts. He stands accused of protecting an intricate web of businessmen, officials and gangsters in this city of 30 million people.

Senior figures from the municipal police department's criminal police and its economic, narcotics, traffic and public safety divisions have been arrested during the crackdown. Various district-level police chiefs and deputy chiefs have also been taken into custody.

Yang's organization was the only mafia-style gang among the 19 targeted during the crackdown that the courts believed did not have police protection.

Yang claimed in court he did not have a source of income and said he was incapable of organizing and sustaining a mafia-style gang.

Courts began hearing the cases last week. Ringleaders from the other gangs are awaiting their trials.

"The city might need to rethink what had made organized gang crimes so prevailing here," 70-year-old retiree Yang Peng said outside the court yesterday.